JPH0159928B2 - - Google Patents

Description

Claim 1: A central bearing device that elastically supports a driven shaft receiving a radial force and an axial force in at least one predetermined direction from a rigid support, wherein: a bearing having a rotatable inner race, a non-rotatable outer race, and a plurality of bearing pieces between the inner race and the outer race; (b) first and second side parts, an outer edge part; (c) an integral lip adjacent to the outer edge and associated with each side to retain the elastic bushing inside the bracket; a bracket relating to at least a portion of;
(d) attachment means for attaching the bracket to the rigid support, the bracket further comprising a flange extending from one of the integral lips, the bracket having a flange extending from one of the integral lips; such that the flange separates a predetermined small distance from the resilient bushing that limits directional movement;
The flanges are connected to the first and second portions of the elastic bushing.
A central bearing device disposed facing one of the side portions on the predetermined direction side.

2. Two soil sinks are provided between the outer race of the bearing and the elastic bushing, each of these soil sinks having a radius of approximately approximately 100 volts to protect different sides of the bearing. an inwardly directed flange such that one of the dirt bays extends between the bearing and the flange of the bracket; and a lip on the resilient bushing extending over the one dirt bay. 2. A central bearing device according to claim 1, wherein said lip forms one side of said predetermined small spacing between said elastic bushing and said bracket flange.

3. The central bearing device according to claim 2, wherein the flange of the bracket is spaced apart from the outer race of the bearing in the predetermined direction and completely surrounds the outer race.

4. The central bearing device according to claim 1, wherein an outer edge of the elastic bushing is bonded to the bracket.

BACKGROUND OF THE INVENTION The present invention relates to a novel resiliently mounted central bearing arrangement for supporting a bearing, particularly a split drive shaft of a vehicle.

In vehicles such as cars and trucks, a front-mounted engine is typically coupled through a drive shaft, differential gear, and rear axle to drive the rear wheels of the vehicle.
Depending on a number of factors, including the distance between the transmission and the differential gears and the angular misalignment between the transmission output shaft and the differential gear input shaft, the drive shaft may be a single member or It may also be in the form of a split shaft having two or more shaft portions, with adjacent portions interconnected via a universal joint. For example, an output shaft from a vehicle transmission is connected to a coupling shaft via a universal joint. This connection shaft is connected to the drive shaft via a second universal joint. This drive shaft is connected to a differential gear via a third universal joint. One or more slip joints are provided on the drive shaft, one slip joint being provided between the connection shaft and the transmission, and the second slip joint being provided between the connection shaft and the drive shaft. Each slip joint accommodates variations in spacing between the transmission and differential gears due to manufacturing tolerances, and also accommodates limited changes in said spacing as the differential gears move with the vehicle rear suspension. To ensure stability of the suspension, it is necessary to support the connecting shaft adjacent to the second universal joint. The axis of rotation is connected via a bracket to a bearing embedded in a resilient rubber bushing attached to the vehicle chassis, frame or body.

In vehicle drives such as those described above, one problem arises when the slip joint adjacent to the second universal joint is prevented from sliding. This problem is caused by lack of lubricant or contamination of the slip joint. In this case, an axial movement is produced in the slip joint between the coupling shaft and the transmission. When this movement occurs, the axial movement of the connecting shaft may pull the bearing out of its elastic rubber bushing, or pull the rubber bushing out of a bracket or housing that connects the bushing to the vehicle frame. Depending on the geometry of the vehicle, the axial movement of the coupling shaft is generally toward the rear of the vehicle.

Various proposals have been made to eliminate this condition. For example, U.S. Pat. No. 3,306,679 shows a resilient mount for a central bearing that resists significant axial movement of a vehicle drive shaft prior to failure. In another construction of a resilient mount for a central bearing shown in U.S. Pat. No. 3,309,154, the resilient mount is capable of rolling axially a significant distance on each side of the support frame prior to failure. can. Although prior attempts have been made to address this potential center shaft problem for vehicle connection shafts, this problem may still occur.

SUMMARY OF THE INVENTION In accordance with the present invention, a novel central bearing arrangement is provided for supporting a split drive shaft connecting a vehicle transmission to a differential gear. This central bearing arrangement is also used in connection shafts in other applications, and is particularly suited for applications where the connection or driven shaft is subject to limited axial forces that pull the support bearing out of its mount.

The present invention provides a central bearing device that elastically supports a driven shaft receiving a radial force and an axial force in at least one predetermined direction from a rigid support, (a) a bearing having a rotatable inner race, a non-rotatable outer race, and a plurality of bearing pieces between the inner race and the outer race;
(b) an elastic bushing having first and second side portions and an outer edge portion to which the outer race is attached; (c) an elastic bushing adjacent to the outer edge portion and associated with each of the side portions; a bracket having an integral lip retained within the bracket and associated with at least a portion of said outer edge; (d) attachment means for attaching said bracket to said rigid support; , a flange extending from one of the integral lips such that the flange separates a predetermined small distance from the resilient bushing that limits axial movement of the bearing in the predetermined direction; , the first part of the elastic bushing
and a central bearing device disposed facing the side on the predetermined direction side of the second side.

According to the invention, the rotatable inner race 42 of the bearing 40 is linked to the connecting shaft or driven shaft 20,
The non-rotating outer race 43 of the bearing is mounted within an elastic bushing 49, which is an elastic rubber piece. A resilient bushing 49 connected to the vehicle frame, chassis or other rigid support via brackets 23, 71 allows limited radial and axial movement of this bearing 40. Brackets 23,71 typically include flanges 70,77 spaced from resilient bushing 49 toward the rear of the bearing. When the connecting shaft or driven shaft 20 attempts to move rearward by a distance greater than this distance, the elastic bushing 4 associated with the flanges 70, 77
9 restricts the axial movement of the connecting shaft, that is, the driven shaft 20. In this way, the axial movement of the driven shaft 20 causes the bearing 40 to move into the elastic bush 49.
or the elastic bushing 49 from the brackets 23, 71. Since the resilient bushing 49 is not normally associated with the flanges 70,77, noise and vibrations from the vehicle drive train are not normally transmitted to the vehicle via the resilient bushing 49 and the flanges 70,77 of the brackets 23,71.

SUMMARY OF THE INVENTION It is therefore an object of the present invention to provide a novel central bearing arrangement for supporting a segmented drive shaft of a vehicle.

Another object of the invention is to provide means for preventing separation of the bearing from the resilient bushing in which it is mounted due to axial movement of the segmented drive shaft of the vehicle;
The object of the present invention is to provide a novel central bearing device for supporting a split drive shaft in a vehicle.

Other objects and advantages of the invention will become apparent from the following detailed description, taken in conjunction with the accompanying drawings.

[Brief explanation of drawings]

FIG. 1 is a perspective view of a vehicle showing the location and use of a central bearing arrangement of the present invention supporting a split drive shaft.

FIG. 2 is a side view of a vehicle segmented drive shaft supported by the central bearing arrangement of the present invention.

FIG. 3 is an enlarged axial sectional view of the central bearing device of the present invention.

FIG. 4 is a perspective view of the central bearing assembly of the present invention with the rubber block separated from its mounting bracket.

FIG. 5 is a perspective view of a modification of the mounting bracket for the rubber block of the central bearing arrangement according to the invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS In particular, as shown in FIGS. 1 and 2, the vehicle 10 illustrated in FIG. 13, a driven shaft, that is, a connecting shaft 20 and a driving shaft 1
1. The transmission 12 includes an output shaft (not shown) of conventional construction and having a plurality of splines around its periphery extending in a direction parallel to the axis. The sliding frame 15 has an internally splined tubular end portion 16. The end portion 16 is slidably associated with and rotated by a transmission output shaft. The sliding frame 15 also includes a frame 17 forming one side of the universal joint 18. Universal joint 1
The other side of 8 is formed by a frame 19. The connecting shaft 20 has an opposite end terminating in a splined shaft section 21 . A central bearing arrangement 22 according to the invention supports the coupling shaft 20 adjacent to the splined shaft section 21 . Central bearing device 22
is a rigid frame or bracket 2 bolted to the frame, chassis or body 25 of the vehicle.
It has 3.

Splined shaft portion 21 at the end of the connecting shaft 20
is fitted onto the inner splined end portion 26 of the sliding shank 27 of the drive shaft 11. Splined shaft portion 21 and splined end portion 26 move axially relative to each other but rotate together. The sliding shank 27 has a shank end 28 forming part of the universal joint 29 , and the drive shaft 11 has a second end terminating in a shank 32 forming part of the universal joint 33 . Frame 34 of shaft 35 forms the second part of universal joint 33. The shaft 35 is the rear wheel 14 of the vehicle 10.
The rear axle 36 is connected to a differential gear 13 which is drivably connected to the rear axle 36.

During normal operation of vehicle 10, coupling shaft 20 rotates and is not subjected to substantial axial forces. When the differential gear 13 moves together with the suspension for the rear wheel 14, the longitudinal movement of the coupling shaft 20 is caused between the splined shaft section 21 of the coupling shaft 20 and the inner splined section 26 of the sliding frame 27 of the drive shaft 11. It happens in However, due to lack of lubricant or excessive contamination, this joint eventually seizes or seizes and no longer performs its intended function. When this happens, the connecting shaft 20 moves in the axial direction, causing slippage in the spline joint between the sliding frame 15 and the output shaft of the transmission 12. The central bearing arrangement 22 of the present invention resists relatively strong axial forces applied to the coupling shaft 20, thereby increasing the tension between the splined shaft portion 21 of the coupling shaft 20 and the inner splined end portion 26 of the sliding frame 27. It is configured to cause slippage at the joint.

The central bearing arrangement 22 according to the invention is shown in detail in FIGS. 3 and 4. The central bearing device 22 is
Rotatable inner race 42 and non-rotatable outer race 4
The bearing 40 has a plurality of bearing parts or balls 41 arranged between the bearing 3 and the bearing 40. Bearing 40
is a chamber 4 surrounding each ball 41 of any ordinary construction.
A sealing piece 44 is provided to retain the lubricant within 5. Inner race 42 defines an internal bore 46 associated with a portion 47 of coupling shaft 20 adjacent splined shaft portion 21 . An annular dirt shield 48 is located on each side of the outer race 43. A dirt shield 48 extends concentrically and proximate the coupling shaft 20 at a slight distance from the sealing piece 44 to protect the bearing 40 from dirt and other road contamination.

The soil shield 48 and outer race 43 are embedded within a resilient bushing 49 or rubber bushing. Rubber piece 49 is mounted within bracket 23 or molded directly into bracket 23. The front edge of the rubber piece 49 forms a lip 50. The lip 50 extends into an annular area bounded by a seal 51 attached to the coupling shaft 20 to further reduce the risk of road contaminants reaching the bearing 40. A lip-shaped portion 52 formed on the rear surface of the rubber piece 49 is bent inward around the rear dirt bay 48 of both dirt bays 48. An additional shield in the form of an oil drain 56 is attached to the rear shaft section 47 of the bearing 40. The oil cutter 56 is
A flange 57 is provided that projects from the connecting shaft 20 to the rear of the bracket 23 in the radial direction. Oil cutter 5
6 prevents water, mud, dirt and the like from flowing along the end of the connecting shaft 20 and into the central bearing arrangement 22.

The rubber piece 49 is shown with two circular rows of spaced apart arcuate slots 53, 54 coaxially surrounding the bearing 40 in the rubber piece 49 in its low elastic state. . When the connecting shaft 20 applies a force to the bearing 40 and moves the bearing 40 radially a distance greater than the thickness of the slots 53, 54, the rubber piece 49
is compressed and exerts a stronger elastic force to counteract such movement of the bearing 40. Each slot 53, 54
is not formed in the bottom region 55 of the rubber piece 49 because the weight of the connecting shaft 20 and the drive shaft 11 is supported by this part of the rubber piece 49.

A resilient bushing or resilient rubber piece 49 is supported within a bracket 23 molded or attached to the vehicle frame, chassis or body 25. Bracket 23 is stamped from a single sheet of steel and has a U-shaped exterior region 60. Region 60 conforms to outer surface 61 of rubber piece 49 . Each end of the U-shaped region 60 has an outwardly facing flange 6 defining a hole 63.
It ended in 2. In the hole 63, there is a vehicle frame,
Insert the bolts 24 to attach the bracket 23 to the chassis or vehicle body 25. Inward facing lip 6
4,65 are associated with the front side 66 and the rear side 67 of the rubber piece 49 adjacent the outer surface or edge 61 to retain the rubber piece 49 within the bracket 23.

According to the invention, the rear lip 6 of the bracket 23
A rear flange 70 is formed radially inwardly from 5. The rear flange 70 is positioned at a predetermined small distance from the rear lip 52 of the rubber piece 49. This spacing is sufficient to prevent the rear lip 52 of the rubber piece 49 from contacting the rear flange 70 of the bracket 23 and transmitting drive-related vibrations to the flange 70 under normal operation of the vehicle 10. I've made it bigger. The spacing between lip 52 and flange 70 is, for example, on the order of 0.06 inches to 0.2 inches or more, depending on the allowable axial movement of coupling shaft 20. In each case, this distance is kept sufficiently small so that an axial rearward movement of the connecting shaft 20 does not pull the bearing 40 out of the rubber piece 49 or the rubber piece 49 from its bracket 23. . Slip Waku 27 and
If the sliding joint formed between the connecting shaft 20 and the splined shaft portion 21 becomes contaminated and becomes stuck, the rear wheel 14 of the vehicle 10, the differential gear 1
3 and the rear suspension system move due to the road surface, the connecting shaft 20 moves rearward. In this case, the lip 52 of the rubber piece 49 comes into contact with the flange 70 and limits the movement of the connecting shaft 20 in the axial direction.
This creates an axial slippage at the joint between the sliding frame 27 and the splined shaft portion 21, thereby freeing this joint and preventing it from sticking at all. This instantaneous contact between the rubber lip 52 and the flange 70 of the bracket 23 should not be felt by the occupants of the vehicle 10 since the suspension of the vehicle 10 also moves at this time. This differs from conventional central bearing arrangements where the main portion of the rubber piece 49 permanently contacts the mounting bracket to retain the bearing. Such central bearing arrangements transmit significant vibrations from the vehicle drive train to the vehicle frame.

FIG. 5 shows the aforementioned bushing or rubber piece 49 and the bearing 40 mounted therein on a vehicle frame, chassis or vehicle body 25 such as the one illustrated in FIG.
A modified version of the bracket 71 is shown attached to the bracket. Bracket 71 is stamped from a single piece of sheet metal to define an outer U-shaped region 72 shaped to correlate with the outer surface of rubber piece 49. U
The end of the shaped region 72 is formed by an outwardly flared flange 7.
Ends in 3. Flange 73 has holes 74 formed therein for attaching bracket 71 to a vehicle by bolts, rivets or other suitable fittings. The front lip 75 is bent inwardly from the front of the U-shaped region 72 and the rear lip 76 is bent inwardly from the rear of the U-shaped region 72 to form a groove for receiving the rubber piece 49. It is designed to form. anterior lip 7
5 is associated with the front side 66 and the rear lip 7
6 is associated with the rear side 67 of the rubber piece 49 to hold the rubber piece 49 within the bracket 71. hole 78
The flat flange surface 77 forming the rear lip 7
6 is connected to the rear part thereof at a distance. Hole 78 is located concentrically with hole 46 in bearing race 42 and is adapted to pass splined shaft portion 21 of coupling shaft 20. When installing the bush or rubber piece 49 into the bracket 71, the rubber piece 49
The rear lip 52 of is spaced a short distance from the flattened flange 77. The rubber lip 52 does not contact the flange 77 during normal operation of a vehicle equipped with the central bearing arrangement of the present invention. Sliding frame 27 and connecting shaft 2
If the sliding joint formed between the splined shaft portion 21 of the vehicle 10 and the splined shaft portion 21 of When moving, it will move backwards. In this case, the lip 52 of the rubber piece 49 contacts the flange 77 and limits the axial movement of the connecting shaft 20. This creates an axial slippage at the joint between the sliding frame 27 and the splined shaft portion 21, thereby freeing the joint and ensuring that it does not seize at all.

The geometry of the vehicle typically causes the bearings of conventional central bearing systems to separate from their resilient mountings in the direction toward the rear of the vehicle in which they are installed. However, if the geometry of the vehicle is changed such that the shaft and the resilient bushing or the resilient bushing and the rigid mounting bracket are separated forwardly, the central bearing arrangement of the present invention can be reversely oriented to prevent such separation. Can be done. If the central bearing arrangement of the present invention is subject to axial forces in both directions, the mounting bracket may include spaced flanges on both the front and rear of the rubber piece to limit axial movement of the drive shaft in both directions. It is set to be limited. Various other changes and modifications may be made to the above-described preferred embodiments of the invention without departing from the spirit of the following claims. Other known configurations for the resilient bushing or rubber piece 49 can be used in the central bearing arrangement of the present invention. The rubber piece 49 may be adhered to the bracket 23 by forming the rubber piece 49 within the bracket 23, or the rubber piece 49 may be a separate piece that slides into the bracket.